1. Field of the Invention
The invention relates to a process for the production of 4-(trialkylammonium)-acetoacetarylide having the formula: ##STR2## wherein: R is H, a lower alkyl, --OCH.sub.3, --OC.sub.2 H.sub.5, --Cl, --Br, --NO.sub.2, --NHCOCH.sub.3 or an anilated heterocyclic ring; n is 1 to 3; R.sup.1, R.sup.2 and R.sup.3 each is an alkyl having 1 to 18 C atoms; and X is Cl or Br.
2. Prior Art
Pigments in the course of their production process aggregate more or less extensively into larger agglomerates. During the working-in of the pigments into the medium of use, the agglomerates must--as far as possible--be split up into their individual components. Almost all characteristics, durability and fastness are influenced by the degree to which one succeeds in deagglomerating the pigments.
In order to improve the capacity of the pigments for dispersion, additives have been added to the pigments during their production. Such hyper-dispersing agents can be, for example, nonpolar systems of polyhydroxystearic acid compounds. For polar systems, polymers, copolymers, longer-chained polyurea compounds, polyacidic esters and quaternary ammonium sulfates, among others, have been used (Progress In Org. Coatings, 5, (1977), 237-243).
In the case of the azoacetoacetarylamide, in order to improve its capacity for dispersion, a part of the finished pigment has been reacted with primary amines. At the same time the keto group in the pigment is converted with the amine into Shiff's base (Progress In Org. Coatings, 5, (1977), 241). The system is imbued with the disadvantage that, on the one hand, it still contains traces of unreacted amine and on the other hand, its capacity for dispersion can be decreased again (flocculations) whenever the Schiff's base is split by hydrolysis.